: : One thing I've always wondered, Nothing with mass can : : go the speed of light...right? : : Ok, so supposedly photons don't have mass, if they did : : it would take an infinite amount of energy to make : : them go the speed of light..right? : : So, then if photons do not have mass, how is it that : : gravity effects them? You know like, blackholes : : have such strong gravity that not even light can : : escape, stars bend light the goes around them and : : so forth... : : Someone please explain this to me... : : Thanks in advance.

: : Dave

: : Light is travelling through the shortest way on a surface and : : the gravity affects the "shape" of the space-time, so light is moving on a bended surface.

: : Antonio

name:crash reply to do photons have mass?

Photons do not have mass, and the gravity of the black hole does not affect light.

The gravity of the black hole affects the spacetime around it. Light always travels in a straight line. In relation to spacetime light bends. We are in space time and it seems to us that light is bending, while actualy it is the space and time around it which is bending.